


Soul Mating

by FullOfBoredom



Category: Undertale (Video Game)
Genre: Double Penetration, M/M, Nightkiller - Freeform, Soul Bond, Soul Sex, Soulmates, Tentacles, killermare - Freeform
Language: English
Status: Completed
Published: 2021-01-24
Updated: 2021-01-24
Packaged: 2021-03-16 01:55:32
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 6,153
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28948524
Author URL: https://archiveofourown.org/users/FullOfBoredom/pseuds/FullOfBoredom
Summary: Night reached out slowly for Killer’s soul, always within reach but rarely so bright, tapping the surface with a fond smile. Killer felt the weight of his words resonate across his being.“Promise I won’t lose you?” Killer grinned widely.“Promise.” The tenseness dropped from Night’s back, arms slung around Killer’s shoulders with a more confident look.“Then take me Killer.”
Relationships: Sans/Sans (Undertale)
Comments: 10
Kudos: 62





	Soul Mating

“Are you sure you want this? With me?” Nightmare wouldn’t meet Killer’s eyes. He stood in front of one of his room’s many arched windows, moonlight shimmering over his blackened form. His tentacles had curled in on him, arms crossed, an uncharacteristic sign of vulnerability that Killer had only seen inside of this room.

“Why wouldn’t I?” Killer, too, let his eternally present grin fall. This matter meant too much, and Nightmare’s insecurity fell heavily on him, on them. 

“Isn’t it obvious?”

“I have an idea, but I want to hear the specifics. ‘s important.” Killer crossed his own arms to match, to hold back the urge to touch his moon until he finished his thoughts.

“Soul mating is to share all that you are with another.” Nightmare turned to face out over the darkened wilds his castle oversaw. “It’s to be unified on every level and live as one until we cease to be. I am not afraid of being unified with you myself; I have centuries of existence and a power to shake the multiverse, and while I’m certain that I will be affected by you, as I am even now when we’re separate, I am also sure of my ability to handle it as I have everything else.”

“It’s me you don’t trust to deal.” Killer sighed, frown downturning further. Nightmare whirled around in an instant.

“I trust you with my life Killer.” He hurried across the room to hold his beloved’s face, a concerned eye looking into Killer’s, begging him to understand. “I would not humor this for anyone else, I would not want this with anyone else. To be joined with you is a dream I wish for. But…” His thumbs wiped away the streaks of liquid hate on Killer’s face. “To be joined to me is my namesake. You will know misery on a level you have never known.”

Killer reached up to hold Nightmare’s hands. He smiled with a short laugh.

“I think I’ve known some pretty deep fucking misery Night.” Killer let go to reach out for Nightmare’s jacket, pulling him closer. “I’m not fragile. You worry too much. ‘Sleeping near me might give you nightmares’ and ‘if I lose control during sex, I could hurt you’ and, my favorite, ‘I am the guardian of negativity, I cannot love you back.’ Yet we’re here.” He took a nice deep breath, sinking into the comfort that was Nightmare pressed to his chest. Nightmare’s fingers clutched at his back.

“Not like this Killer, never like this.” Cyan tears welled up, hands vice gripped onto his hoodie. “I am not minimizing your suffering, I have felt it firsthand, but mine is long and continuous. It bores into your soul and lives there. You mention that I have always worried and you have overcome, but yet, I still worry. Negativity is at the root of me.”

His tentacles reached out like more arms. The fear was palpable, flavoring the air and thick on their tongues. Nightmare could never forsake what he was. He could not undo what had been done.

“And to join you with that? I’m afraid of what this could do to you. Will you gain my corruption? Will I lose you like I lost myself for all those years? How much of you must be traded for us to experience this pinnacle of connection?” Night’s words flooded from his mouth, crying bitterly at the thought of turning Killer away, all for his sake. “Every single thing others can have, I must first pay a cost. To just exist without punishment cost my life, my home, my family. And even then, I did not escape punishment, I merely gained the ability to fight back!”

“Nightlight…look at me.” And he listened. Killer tapped his teeth to his.

“Killer…” Nightmare tapped back, kissing him deeply with wet cheeks. The tension of the room could be cut with a knife, Killer could feel it in the line of Night’s back, and he knew how to work that out. When they broke apart, Killer didn’t move back an inch.

“Remember when you confessed?” His voice rough and heavy against Night’s teeth, Killer’s eyes went half lidded. “You looked so shocked, like you couldn’t believe it.”

“I still don’t.” Nightmare’s voice dropped low, shaky but wanting.

“Moon, are you happy, being with me?” Night’s tentacles clutched him tight, Nightmare pressing up tight to him with another kiss, their faces still millimeters apart.

“Of course. Idiot…” His eye glanced wistfully at the bookshelves on the wall, expression serious and hesitant. Killer chuckled softly at the worry. He wiped his god’s tears away.

“Then why couldn’t I be happy joined with you?” Night’s body sparked with magic underneath his fingertips. “If even the god of negativity can be happy with the one he loves, why couldn’t I do the same with a piece of him living in my soul?” Killer licked his teeth, tongue touching his moon’s at this distance, groaning at the catch in Nightmare’s breath.

“You could.”

Killer crushed Night up against him, the smaller hands fisting in the loose blue hoodie in their passion. Kissing Nightmare always got his motor running. His dark tentacles sought out every surface to lavish attention on Killer’s body, three times the stimulation of any other partner and a hell of a lot more interesting.

“Let me have ya then.” His pointer finger slid down the black cheek, catching softly on his jaw, over his sensitive throat, and leaving a hot trail of need down his sternum before halting. Right over Night’s soul. “Mate with me Moon.”

Night reached out slowly for Killer’s soul, always within reach but rarely so bright, tapping the surface with a fond smile. Killer felt the weight of his words resonate across his being.

“Promise I won’t lose you?” Killer grinned widely.

“Promise.” The tenseness dropped from Night’s back, arms slung around Killer’s shoulders with a more confident look.

“Then take me Killer.”

Killer had a slight height advantage, but Night made up for it with vigor. The black fingers pulled at the hoodie, growling when Killer laughed at him for its slow removal.

“My soul’s not inside my ribcage Moonlight. Did ya forget?” He chuckled until Nightmare pulled their faces together again, groaning into Night’s mouth, tasting and teasing the cyan tongue until he felt Night’s fingers loosen. He took the opportunity to run a phalange up from Night’s back to his sternum, tracing a rib. Night broke off to shiver.

“Are you trying to rush?” Nightmare traced the outer edge of the target shaped soul. It snapped into a heart shape for the second go around. “There you are.”

“I just like when ya touch me.” Killer winked, grinding up against Night’s pelvis. Night bucked against the bulge in front of him. He kept rubbing the tiny heart in his hands while Killer nuzzled into his throat to nip and lick at the sensitive vertebrae there. “Fucking delicious. Can’t wait to have ya.” Killer took a deep breath in, lost in the scent of Nightmare. 

Night didn’t respond, only kissed the soul in his hands, trying to impart what he couldn’t say. _I’m the lucky one. That you want me, it matters more than anything else._

Killer’s mouth licked haphazardly. The warm buzz of emotion from Night seeped into his body, unfurling the little anxieties building in the peripheral of their relationship. Killer put on a grandiose show, playing the part of the cocky bastard to his moon’s calm stoic, but Nightmare very rarely opened up this far. His moon cried less than Killer had fingers on one hand. He spoke seldomly about the past in anything but factual recounts. The fact he’d been so honest, that he could feel that pure emotion through the contact, put him in a drunken euphoria. 

“Moooooon, you’re wearing too many clothes.” He pushed the hoodie off Night’s shoulders, caught on his elbows. “Come to the bed.” Killer slid his hands up to hold Night’s hands, soul dropped and returned to its place.

Killer led him towards the bed, but let him go with a sly grin. He stripped off his shirt with a twirl, revealing his ribs with hungry eyes, dropping his shorts in the next moment to persuade his love to do the same.

“Eager, are you?” Nightmare’s voice betrayed nothing, but the slow shrug off of his sweater spoke volumes.

“Already missing that touch of yours.” He gestured to his soul. “I could get off from just that.”

A peace offering, a way to back out, to build to this piece by piece. Night stepped closer to his love leaned back on the bed.

With a determined eye, he skimmed over the bulge of Killer’s cock, meeting Killer’s captivated gaze with ferocity. He only broke it to remove his suffocating shirt.

“Ignoring my needs? What type of mate do you plan to be?” Killer’s eyelights popped into existence while Nightmare seated himself on his lap. “I thought you said you’d never disappoint me…” He almost fell off when Killer sat up to meet him, smashing their teeth together.

Killer dove in, not leaving room for Nightmare to fight back, overwhelming his small lover with how much he could explore with his eyes closed. They were both pantless by the time Nightmare’s senses returned, breathless but alive with energy.

“If you’re feeling needy, we’ll focus on you then.” Nightmare had no ecto formed yet, Killer instead reaching up into his chest for the dark apple soul he’d never been allowed to touch. His hand hesitated before tapping the blackened surface. “Last chance Nightmare.” And when all he got was silence, he took it out and held it up to his face.

Unlike his own soul, the black apple sat calmly in his hand. It had little give, the dark peel a thin barrier to protect it from the outside world, everlasting and unbroken until this very moment.

“Didn’t expect that.” Killer ran his thumbs over the surface, testing the limits of the shell and Night in one swoop. His moon sat unaffected except by a blush.

“I’m sorry it’s not what you expected.” He could read Night’s hesitation in his body language, but not from the soul seated in his hands, its aura as calm on the exterior as its owner. He wanted in. Killer gently bit down on the apple, not wanting to go clean through, but maybe create a little breach. When Night didn’t react, he bit down harder. His ectobody formed instantly, boosting him up on Killer’s lap.

“OooooooH!” He broke the skin, a small cut through the outer barrier. Night hadn’t ripped it away yet, so Killer turned it over until he could work his tongue into the hole.

“KiLLeR.” Night’s thighs tightened on his legs, hips bucking down wantonly while his cyan tongue lolled out of his mouth. Killer kept working and tasting, getting deeper and deeper into the soul. “STARS, Killer, please. Fuck me!”

Tentacles curled up every limb stroking and teasing. They sought out Killer like a moth to the flame, knowing who was pleasing their master, eager to return the favor. Killer appreciated their caress, but focused in on the torrent of emotion pouring into his mouth from the apple. Night’s composure seldom broke outside of the bedroom, and even here, he was not driven to utmost debauchery, often just more openly honest about his desires. Licking directly into his core, Killer could taste how much Night was holding back. He sucked out some of the wet flavor with a slurp.

“God ya want this so bad. Good, me too.” Killer worked two fingers into the break to Night’s wrecked gasps. “My soul can’t fit in here love. Gunna have to make room for me inside ya.” 

“I need you inside me, right now.” Night’s tentacles readjusted them quickly for his red cock to slide up and down Night’s already wet folds. “I love you, connect with me, I’ve got so much room for you…” Killer heard the wet squelch of Night stretching himself open with a tentacle in preparation, making his cock twitch in anticipation. He forced his tongue in around the three fingers he’d worked into Night’s soul. His reward was instantaneous. 

“AAH!” Night’s knees knocked on his waist, his eye wide and hazy, which Killer took advantage of by pulling Night further onto him and starting to sink into his soaked pussy along with the slicked tentacle still stuffed inside. 

“Oh FUCK!” Night’s cyan eye rolled into his skull, trembling apart at the seams. “T-they fit?”

“They sure do.” Killer pulled his soul up to the opening in Night’s. “You ready for the second squeeze?” He flexed his hips making Nightmare scream.

“Stuff me full Killer, hah, please!” 

With a gentle push, his soul tapped against the inside of Night’s, the opening worked large enough for the entire thing to fit along it on one side. He watched fascinated. Normal soulmating, you could hold two souls together and they’d combine, no work required but the desire to do so, but he had to try at getting his moon open enough to reach the savory core. They sat against each other for an instant, Killer anxious if he’d gone about it wrong and Night if he could even do this at all, before Killer’s entire soul slid directly inside, combining them in a flash of color.

The red apple hung between them pleasantly. Killer’s eyelights glowed bright as Night’s went deep purple.

“Moon?” The words echoed in his mind, though it felt like he spoke them. He didn’t need to say anything, Night was him and he was Night, but his sudden desire to hear Nightmare overrode logic.

“My darling soul.” Hands rested on his face. Night’s locked eyes with his, faces moving closer, but even an inch felt too far. It was slow deliberate love, that first kiss, the taste of their soulmate for the very first time.

But then Night shifted to get a little closer and the thickness inside him sparked the desire.

That spark quickly caught, burning through both of them with the intensity of sun, each thought echoing between their souls, escalating to a constant hum that drowned out the rest. Night slid forward to take Killer and his own appendage to the hilt. Killer moaned loudly before pulling Night up to his chest with a desperate kiss. He could barely get out any words.

“I love you.” It slurred from his teeth, feeling the tentacle inside of Night curl around his cock to make it stretch out Night wider. “You’ve got my soul inside yours, ya shouldn’t mind if I fill ya with my cum right?” He thrusted experimentally; Night wailed and slid down to meet his hips. His purple blush complimented the wrecked expression, staring into Killer’s eyes like a lifeline, before nodding with a broken moan. “Fuck you’re perfect.”

He started slow. Night winced at the end of the thrusts and Killer wasn’t so far gone as to not notice; to the contrary, he had never been more aware of his moon. The sound of his voice breaking on Killer’s name a symphony, the taste of his love’s tongue a banquet, all his senses awakened at the sight of his gorgeous soulmate. And through the bond, he could feel Night’s agreement.

“Please, please, please!” Oversensitive and at the emotional limit, Killer could feel his peak rapidly approaching, speeding up to slam into Night, clapping their ecto together between lewd pants and groans. He dropped his sweaty head against Night’s shoulder.

“God Night, come for me!” Night’s pussy clamped down tight with his orgasm. Killer rode it to his own finish.

“Fuck!” 

He slow thrusted through it, filling up Night with his red magic, sliding against each other with pleasant bonelessness. They fell back onto the bed in their embrace.

“Killer…”Night’s head rested on his chest, one hand rubbing over where he could see Killer’s cum inside himself. Killer felt tears drip onto his ribcage.

“Nightlight?” He cradled Night’s head. He held him tight, Night nuzzling his chest with the rarest of expressions.

“Thank you.” The genuine smile, soft and sweet, hit Killer right in their combined souls, overcome with their combined joy. He had it so bad. They readjusted to separate, sharing soft continuous kisses, settling into the blankets with unmatched contentment.

“We look pretty good together.” He stroked a finger over the red apple, both trembling with a soft sigh. “Can’t get rid of me now. No take-backs.”

“I can think of no better partner for eternity.” And that deep honesty flustered Killer. He hoped he’d get to see more of this side of his beloved moon now that they were one. Being one in all forms had unlocked more of himself than had existed before, parts he would adopt from Night starting to click in as extensions of his soul. Something dark ate at the back of Killer’s mind, but combined like this, it was held at bay effortlessly by Night’s calm thoughts and breathing.

“Let’s get some rest Nightlight. We have the rest of our lives tomorrow.” He pulled up a sheet to cover them, and placed one last kiss on Night’s teeth. 

“That we do.” With their combined souls hanging between them, they slipped in restful sleep. 

-

Killer woke up late. Looking around, he realized he’d been moved from Night’s bedroom to the study. He sat up (appropriately though not fully dressed) on the lounge that Nightmare had scooted closer to his desk.

“Good afternoon. How are you feeling?” Killer felt strangely apprehensive before realizing that the feeling wasn’t centered in his body. The immediacy lessoned the longer he thought about it, though the intensity of that wariness kept ratcheting up while he tried to speak.

“Is that you?” The sudden break in relief caused emotional whiplash and a spike of discomfort.

“Yes. My apologies, I wasn’t reigning in my reactions.” The normal calm came back, with a background fluttering of too many emotions to name. “It should be more manageable now.”

“Wow, I must be bothering the fuck outta you.” He laughed at the tinges of worry, indignation, and relief in turn. A glance at his own chest revealed only his own soul. They’d separated when sleeping it appeared.

“Always.” 

“Wow, this is what you’re actually feeling?” Each emotion felt so distinct and different, the deep fondness manifesting as a touch to the cheek and a soft smile, the yearning a waltz across a marble floor, remaining a respectable distance but waiting for a moment alone to close the distance. So caught in this tide, he didn’t notice the tentacle resting along his back.

“Yes. I hope you could see through the sarcasm beforehand. But focus for a moment.” The appendage slid up his spine, Killer shivering. “I’m syphoning my power out of you by force, but once I break contact, you will be hit with whatever my corruption has done to you.”

“Still worried?” Killer grinned with a tilt of his head, shit eating smile not calming Night in the slightest.

“I didn’t want you to wake up in whatever state this will put you in. There’s a difference from knowing it’s coming to waking up overwhelmed.” Killer rolled his shoulders to ready up, taking a few breaths before nodding confidently. 

“Hit me with it Nightlight.” 

The instant the words left his mouth, the weight of the corruption fell on his back. He gasped, choking on the weight of the atmosphere, hate spilling out of his eyes. His soul pulsed heavily, weighted and overwhelming, drowning in a pit of self-loathing and anger that he almost couldn’t see through. 

He fell off something. His hands scrambled along the floor, colliding with something that Killer clawed at until he was sat up again.

He trembled violently, bones clattering against his leverage. Sounded familiar though. Where had he heard it before? He focused on the sound to anchor himself in the moment, reflecting on it until the answer came to him suddenly. Nightmare’s desk, he’d had sex on enough times to remember the way wood sounded banging against bone.

Nightmare! He’d been with him before this.

Killer heaved in a few gulps of air. If he reached out with his magic, he could feel him, dark and powerful not too far away, and that helped get through the worst of the panic. The calm washed over him like soothing rain. It soaked into his joints until he laid back against the wood, completely still.

Amidst the black came a single bright ping of light. Hope lit in his chest like a lamp, illuminating his eyelights, finally able to see.

Feelings were too overwhelming to speak, but his staticky pupils stared at his moon’s face.

Nightmare forwent his usual propriety, his normally impassive face scrunched up in unease. His cyan pupil took in every movement, any motion or emotion he could see. Every tentacle hovered around him worriedly, barely restrained from touching Killer to sap the feeling away. He felt Night’s palms on his. He gripped them back with a tired grin.

He could see Nightmare trying to speak, but his ears hadn’t caught up to him yet, still roaring with the stress his body had gone through. He tugged on Nightmare’s arms, toppling the king to the ground into him. Pressed against his chest, he felt better already.

Oh look at his cute soulmate. God he loved him.

Night had been knocked down to kneeling over Killer’s collapsed form, sitting in his lap with flushed cyan cheeks, all right in reach of Killer. Night really should know who he was dealing with by now.

Killer kissed him fully, hands trailing to his shoulder joints to get his moon to huff and let him in. It felt incredible, their magic tongues sparking up pure passion between them through the bond. The fog from the shock of Night’s power was clearing, getting further and further away the more he touched his precious mate, measured in the volume of sounds finally reaching him. By the time they broke apart, Killer had his mind back enough to speak.

“I told you. You worry too much.” Killer grinned, eyes closed and amused. He nuzzled Night’s cheeks with his own. “If you think I was handsy before, you won’t be able to handle how much I want ya now.”

“You’re incorrigible.” Nightmare surged up into another kiss. The magical connection pulsed alive in their souls, swept away in the insatiable urge to be closer to each other. So enraptured that they only halted when they heard mumbling to the side.

“I’m not interrupting them Papyrus, they’ll take a break eventually…” Dust didn’t even flinch when their eyes snapped over to him.

“Didn’t take ya as a voyeur Dusty!” Killer laughed. Nightmare stood quickly, but didn’t move to take his place behind his desk.

“I suppose you’re reporting in on your latest assignment in Fellswap.” Night could compartmentalize like a pro, his face blank and unaffected in moments while Dust relayed his findings calmly. Killer had envied Night’s ability to sort away emotions and reject them, choosing to feel them instead of being overcome, but now that he had a direct link behind the facade, he found himself awed at his moon’s composure under enormous influence.

Calmed by the impromptu make out session, Killer searched inside himself for what was new.

The parts of the bond that came from Nightmare felt shiny, not like the pieces that had always been there. He could feel those rotting things from his own past had been broken in, worn to match the rest of him, unlike that which was added. Killer visualized Nightmare’s power like a tiny galaxy living in him. Dark and expansive, powerful and captivating, it crooked a finger at him to indulge in the negative in himself and in others around him. He could pull on it, indulge in the poisonous vapors, become more powerful in an instant. 

Tentacles slithered over his arms, lifting him carefully but pulling his back flush against Nightmare’s chest.

“Now where were we?” Night’s voice rumbled through the both of them. Killer stroked each appendage and licked the corner of Nightmare’s mouth.

“Almost to the good part.”

He was level 20. Right hand of the terror of the multiverse. Mated to the god of negativity. He’d killed plenty and taken what he wanted his entire life. 

Killer shut the power out of his mind. He’d take it in stride and learn to tame the damn thing. No need to throw away his sanity for more power than he already had, especially not at the cost of his moon. 

One stray hand to his pelvis and the thought was gone.

-

“How do ya deal with the cravings?” Killer’s hand clenched around his knife, breathing through his nose in metered breaths. Blood red magic ran from his mouth where he’d bitten his tongue at the last second.

“I indulge when it is safe to do so.” Night watched cautiously from the door to the training room.

“And when’s that?” Killer curled in on himself.

“Moments like right now.” 

He and Horror had been sparring, just like normal, taunting back and forth, when the corruption had reared its ugly head mid-sentence. 

_“Can’t keep up? Maybe that’s why you couldn’t feed Pap-_ ” Killer instantly ate his own words, teeth cutting clean through his tongue before Horror could do anything in retaliation. He didn’t even block the attack Horror had started. They weren’t fragile, god knows that they had tougher skin than most, but there were lines you _did not_ cross, and Killer had sprinted straight past them without looking back. He hadn’t moved since.

“So you’re feeding off my fuckup? At least that’s something.” His shirt was wet against his sternum, stuck and soaked in the front, sticky and thick on his fingers tearing into the fabric.

Nightmare pulled down, sitting beside him on the floor. Every limb hovered over Killer’s form. Times like this, he almost detested Nightmare’s superior control, unable to see beyond that carefully neutral face and the wall Nightmare could pull between their bond with ease.

“I cannot help my nature. That doesn’t mean I wished for this.” Nightmare folded his hands in his lap, a picture of patience. “He has already forgiven you.”

“He fucking shouldn’t. I knew what the fuck saying that would do.” Killer sneered at the floor. Black dripped down to mix with the crimson staining his clothes. He was such a piece of shit, giving in like this was his first damn rodeo, like he’d never had to exert ANY fucking self control! He fell forward until his face met the floor.

“You’ve only had this power for a few weeks. It takes time.” Killer could feel his tentacles tentatively soothe him at the edges, pokes and pats soft enough to be shaken off should he decide to run. “I’m sorry.”

Killer’s eyelights flicked on at the tiny pulse of sadness. Night could hide a lot, but powerful swings couldn’t be hidden from your soulmate.

He turned over to stare at his moon. His face looked steady as always, but knowing the emotion beneath gave it away. Night met his gaze evenly, but his eye had gotten soft, rounded on the edges. If he looked closely, tension pulled Night’s arms taut, elbows pressed too hard into his lap, tiny tremors in the forearms from pushing his stress to a hidden place most wouldn’t notice. Really seeing it had Killer shuffling up to sit again.

“Moon, I don’t regret anything. I’m mad at myself but not at this.” He sought out Night’s folded hands, grasping them with his dirtied ones. “The only thing directed at you is that you still keep hiding from me.”

“It’s…a lot to handle. You already feel overwhelmed, so I…”

“I get to decide when it’s too much Nightlight. Tell me how ya really feel.” The revulsion from his actions faded away, patiently waiting for Night to let down the wall.

It dropped all at once, a dam cracked open over his psyche, Killer awash in a million emotions, many that didn’t have names but ate at him sharply. Another piece of him soaked it in, eating up all Night’s doubts and self-loathing with glee. Killer flinched.

“It feels weird as fuck to like when you’re upset.” Killer scrunched up his face. “I prefer you smilin’. Or moaning.” He gave Night a saucy wink. His reward, a light peal of laughter, lit his soul up like a glowstick. Night cupped his wet face with a soft smile.

“I’d like that too.” A chaste kiss melted the dark atmosphere away, Killer left besotted in the wave of fondness from his lovely moon. “I will always feed on the negative, but in this, I gain strength from our love too.” He hummed softly at Killer’s enamoured look. “In sickness and health, my soul.”

The kiss was warm, but not drawn out. They were still in the training room after all.

“I guess I should clean up and apologize to Horror. Even if he forgives me, don’t mean I don’t have to apologize.” Killer stretched back. With a swing of his torso, he landed on his feet. Night stood to join him, resisting the urge to take him elsewhere for soft reassurances. “See ya tonight light?” Killer stuck his tongue out.

“It isn’t optional.” Night pulled him forward with a single hand by the collar of his hoodie. “I’d hunt you down if you tried to stay away.” His seductive smile made Killer purr.

“Hunt me down then Moonbeam. I look forward to it.” The pleasant shimmer of emotion under it all warmed his bones as he walked to his room for a change of clothes. Killer caught a glimpse of the hall mirror, taking in his wrecked appearance with little concern. With each day, he owned more and more of this new darkness, and one day soon, he’d have eternity left with Night. He flexed his arms to rest them behind his head.

“Now where is Horror?”

-

“Take Horror and get the fuck out of here.” Killer swung his blade through an ink stream. It deflected off to the side, narrowly missing Dust, who had Horror up over his shoulder.

“You can’t take Ink and Cross alone idiot.” Dust had started to back towards the exit anyway. He’d save two skins over one any day.

“Don’t need to take ‘em. Boss’s on his way, just gotta run out the clock.” His grin widened as he turned back to his opponents. The liquid hate began to pour from his sockets, dripping onto the floor, starting to puddle into pitch black pools. He slid his knife under the waterfall to coat it in the black sludge. “And I’ve gotten better at taking my time.” When he stepped forward, Cross stepped back.

“What’s the matter? Don’t tell me you’re _afraid_.” 

“Not a bit.” Cross’s stance shifted to put his blade between them. He kept readjusting his grip on his weapon, anxiously preparing for whatever new tricks Killer had up his sleeve. “I’m not so easily shaken.” His white eye went gold.

“I don’t think that’ll make that much of a difference.” Killer flipped his knife with ease, taunting his favorite punching bag of the Stars. Internally, he checked his balance to dodge positivity arrows. “Whatcha gunna do? Stare at me?”

Cross swung confidently in a forward dash. Killer jumped out of the way.

“I’ve got positivity on my side.” Killer almost laughed, but a shot of ink missed his face by an inch. 

“And a little help!” Ink chuckled, setting himself up around the edges of Cross and Killer’s spar as inconvenient back up. Killer blocked a direct attack, focusing his energy to spread the corruption over to Cross’s blade at point of contact. The gold eyelight flickered until Cross whipped back.

“What the hell did he do to you?” Cross curved the sword to smash into the ground with a grimace. The sludge cracked and crumbled off.

“It’s better than the nothing Dream gave you.” Killer stuck out his tongue, enraging Cross into re-engaging. 

Cross hadn’t gotten much better. His stamina had increased, drastically so, but so had Killer’s, that wasn’t making the difference. Cross stepped into the sludge pool, sliding off balance. Killer pounced on the opening. The back up ink stream caught his shoulder. He growled at the shot of pain but poured that feeling into his spark, bouncing back before Cross could even react.

Even the help wasn’t making that much of a difference. Cross just wasn’t messing up as much as usual.

Cross had always left openings in his attacks, and Killer exploited them, which upset Cross, which made him fuck up more, which made him an easier target, ad naseum until he kicked his angry, self loathing ass. Looks like he’d gone and gotten with Dream to get over himself. Well mostly, because he was still fucking up, but each success powered the positivity and that weakened Killer now, even as his own worries ate at him. It was the world’s worst snowball effect. Too absorbed in his own head; he found himself backed into a wall.

“Look who’s cornered now?” Killer _hated_ that smile on Cross. Well, he’d either have to take a scalding or a slice to get out of this. He leaned back to push out of the corner after the swing.

“Try not to get my face. Boss’ll have no eye candy at the castle.” 

“Well we can’t have that.” The sight of the tentacle gripping Cross’s knife made him swoon.

“W-what?” Cross’s eyesight dimmed back to white with Night’s touch. “How’d you get here so fast?!” Nightmare tilted his back towards Ink.

“Killer.”

“Yes Boss.” He took off towards the painter like a bolt, powered by the Night’s aura and the dread Cross eeked over the battlefield. He listened to Nightmare’s talk while easily keeping Ink busy.

“The better question, Cross, is why Dream has not come to save you. Are you just not worth saving?” He’d wrapped Cross in his tentacles, the spark of positivity being drowned out by the overwhelming panic, much tastier than normal loathing. “Did you think you could take him alone? Did you doubt that I’d come to defend what’s mine? Or is it…you can’t call him?”

“I can call him!” But no one came.

“Don’t forget who I am. I am not easily deceived.” Night’s satisfied smile drilled into Cross’s mind. “Such a pity. He mates with you but doesn’t tend to your spark. What a waste.” He tightened his hold on Cross, wincing at the tightening pressure. “Killer can call me from any corner of the world if he chooses. He can wield my gift. You were left with nothing but the promise of feeling better, while I raised my mate higher.” Night manipulated Cross to stare at him in the eyes. “Dream truly does not understand his own power, and, by extension, you.” Condescending and conceited in turns, though Killer could feel the pride beneath.

“You and Killer?” He’d barely gotten it out before his eyelights blanked.

“Not your concern.” He’d seeped most of Cross’s strength away before throwing him towards Ink disdainfully. He broke off his fight with Killer to look over at the limp offering. “I suggest you get him out of my sight. I will not spare him a second time.” Night turned away from the crumpled heap, wrecked traitor gone as soon as Ink grabbed him.

“If I said I wanted your body now, would ya hold it against me?” Killer held his arms wide open. Nightmare walked directly into them, not even waiting until Ink had fully portaled, kissing his mate fondly.

“Have I told you that you can be insufferable at times?” Killer laughed so hard he could hardly stand up straight.

“I know I’m your favorite. No need to say anything.” With a hand to guide Night on his chin, Killer angled into another kiss, soaking in the love and affection from his moon as easily as he had his worries and troubles. Nightmare rested easily between his arms, happier than Killer had ever seen and proud beyond measure of HIS soulmate.

“I love you. You are, indeed, my favorite.” He leaned into Killer’s chest. “Now, how about we go home for some _preferential_ treatment?”

“Moon, you just read my mind.” Killer wrapped an arm around Night’s waist, sliding the other hand along his arm until he had Night’s clasped off to the side. A perfect dance pose, Night shaking his head with fake exasperation, straightening to press against him. The portal whirled open somewhere behind them. “Let’s waltz on outta here.” Night laughed.

“Lead the way Killer.”

He grinned and waltzed them right through the portal, to home.


End file.
